A common feature present in typical implementations of data storage system enclosures is the midplane. Generally, a midplane is a multi-layer printed circuit board that provides interconnection among the various modules in the storage enclosure, such as storage disk drives and control boards. Inserted through front slots of the enclosure, storage disk drives connect to one side of the midplane; control boards connect to the other side of the midplane from the back. Over signal paths constructed into the midplane the control boards communicate with the storage disk drives.
Enclosures employing a midplane have certain disadvantages that can impede the development of low-cost data storage systems. Apart from manufacturing costs associated with a midplane, the electronics of the midplane also has associated reliability and repair concerns. Typically, the midplane is “tuned” to perform optimally with the control boards and disk drive modules in the storage enclosures. Problems with a midplane can require its replacement. However, whereas the task of installing a new storage disk drive through a front slot or of replacing a control board through the rear side of the enclosure are relatively easy to perform, replacing or retuning a midplane often requires the burdensome task of disassembling the enclosure itself. Moreover, a midplane can occupy a sizable area within a data storage enclosure, thus placing a limit on the minimum size of a data storage enclosure design. Thus, there remains a need for a midplane-less data storage enclosure that avoids the disadvantages of having a midplane.